The HV30 only accepts
mini SD cards. They're NOT the same as micro SD cards. (Manual here:
https://files.canon-europe.com/files/soft31927/Manual/HV30_CUG_ENG.pdf ).
Mini SD cards are quite hard to come by these days, as their maximum capacity is only 2 GB. To the best of my knowledge, only used cards are now available. If you want to buy such a card though, see here:
https://www.ebay.co.uk/itm/284183649040
Since the HV30 was only designed to be used with a maximum memory capacity of 2 GB, it's impossible to know whether it will actually work when more memory is available to it. (Many devices have a maximum memory size that they'll work with). However if you want to give it a go, you can buy a mini-to-micro SD card adapter here:
https://www.ebay.co.uk/itm/112458281078 .
You'll then need a micro SD card to go into it. I buy mine here:
Amazon.com User Recommendation